backgroundItems: [
 {content: 'Forbidden Period 1', start: '2023-01-01', end: '2023-10-01', type: 'background''},
 {content: 'Forbidden Period 2', start: '2024-01-01', end: '2024-10-01', type: 'background', bgcolor: 'rgba(255, 0, 0, 0.2)'},
 {content: 'Forbidden Period 3', start: '2025-01-01', end: '2025-10-01', type: 'background', className: 'negative'}
]